Device for effecting the automatic movement of the material in sewing machines



Nov. 22, 1938.

R. c. ROBERT 2,137,857

DEVICE FOR EFFECTING .THE AUTOMATIC MOVEMENT V OF THE MATERIAL IN S EWING MACHINES Filed Deg. 1, 1936 Patented N... 22, 1938 t 2,137,857

UNITED sures PATENT OFFICE.

MOVEMENT OF THE MATERIAL IN SEW- ING MACHINES Ramon Oasasltobert, Barcelona, Spain Application December 1, 1936, Serial No.113,538

In Spain September 23, 1935 p '6 Claims. (cilia-210M This invention has among its objects to proof the movement 01 the toothed member be vide means for eflecting entrainment or auto+ changed but also the direction of the movement. b matic advance oi the material in sewing ma- The essentialieature of the device according chines. l c i i to the invention is that the complete movement i It is known that sewing machines are formed, of the toothed member is eflected by means of g in the platform or arm on which the sewing is a single triangular eccentric so constructed that. ne and in the zone or the'reciprocating movein the course of two non-consecutive quarters of merit of the needle, with an aperture across which its revolution, it eflects respectively the advance is projected'a toothed member which follows a and the return .of the toothed member and that, rectilinear path, that is to say, a path comprising in the course of the two other .quartersoi its 10 a, h rizontal portion, the teeth being then above revolution which arealternate with reference to the level of the platiorm and then a substane qua ters oit e revo ution fi s e t oned. tiallyvertical downward portion, a further horlit efl'ectsthe necessary ascending and descending zontal portion but in the reverse direction to the movements of the toothed membern 16 first and below the platform, finally an upward The device according to the invention is also substantially vertical portion. During this phase c ct ed y e feet thetthe teethed moiqthe movement, thetteeth oi the member reher is displac d about i P v Pblnt 50 that its ferred to grip the material which is being sewn feed and return movements are eflectedwhile deand which is thus entrained during the first scribing in each case an arc 0! a circle and its 20 horizontal movement, by reason of the pressure ascending and. descending movem ere 20 i of the springwhich' acts onthe presser ifoot of iected alon fl iwi 0 h sai r the machine and causes it to bear against the i :The device accordinl t0 t invention 18 eteeth. This operation is eflected while the needle a ca y illustrated. y y f. p e. n is in the raised position. 1 the accompanying drawinga, The means referred to are provided with de- Figure 18 lohl'itudlhal sectional elevation 26 vices for varying theadvance of the material. of a sewing machin h -vinsaneedle pletemeunt:

In certain modern sewing machines, the direction ed on arm and the device to which the l of this movement can also be reversed according Ventien r p i to the position occupied by the person operating Figure 2 i a transverse sectional elevation of 30 the machine. V the arm. i i

, The devices used, as well as the mechanisms Figure 3 1s a diagrammatic View of the which actuate them and the. controlling and op- Vice with Krapmcal representatmn 05 its 9' erating parts with which they are provided,'are emtmni i l a very complicated, are difiicult to construct and to Figure 4 1s Perspective View nmdmed I assemble and are dimcult and complex in working Of the mechanism a and are liable, on account or their complicated The e e np d to sewins machines constructiomtobe easilyda'magedand to make which have-fit their lower p that 1 y a noise and to vibrate because they :are made below their P a or alongitudinal shaft which up'of such large and heavy m b is given a rotary movement. 'Rigid with this The device according to the invention is dis- 5113, which is designated by the reference 40 anguished by its compactness, which renders, it merall is atriangular eccentric 2 which actuate:

effective for use in the most diflicult cases and a connecting rod 3 provided with square hole chiefly in machines in which the'needle plate is themntm 2 exactly" I The other end of the connecting rod 3 forms a mounted not on a platform buton an arm, which 7 facilitates various types of work, since it is slide member positioned between the guides 8 5 t .i I connectin sible, by reason of the small section 01 the arm, r52 K2 2335213? a g 21: 3 m tomtmduce the m t garments which forms the slide is circular; in the circular upper a being, sewn even Where they have a tubular part is secured a spindle 5 normal to theplane form as in the case 0! sleeves and stockings. the connecting o tha spmdle 5 m w T e c e ns o the invention is a mounted a link a which is also mounted on ancharacterized by its extreme simplicity not only th mdl disposed-parallel to the spindle 5. as regards construction but as regards control Th di t n separating the geometric axes of and operation since, by means of a simple conthe spindles I and I is the same as the distance 55 trol handle or grip, not onlycan theamplitude separating the spindles I from a shaft 0 from 55 which the spindle l is carried by a member 8 lying parallel to the link l and secured at one end of this shaft 9 which extends the whole of the length of the platform of the machine and is mounted so that it can rotate through a determined angle. To the shaft 9 is firmly secured an arm l0 which projects above the platform as shown in Figures 1 and 2 but which may equally well project laterally. The arm I ll ends in manually operable adjusting means formed 'as a screw H with a knurled head which screw can be made to move up or down as desired and can be held stationary at the desired height by means of a lock nut ll The point of the screw l l bears, when the arm I0 is displaced, against a flat, fixed plate I2 which constitutes the geometric chord of the are described by the point of this screw H and which, furthermore, is greaterthe further the pointed end of the screw is from the shaft 9. This allows the inclination which the arm It can assume to be varied and, thus also the inclination of the member I which displaces and carries the spindle I, in order thus to vary the stitch and the direction of sewing. The mechanism described which serves to displace the spindle 1 around the shaft. as centre is secured in the sewing position desired by means of a spring formed in the present case as a rectangular steel plate II, which is curved and provided at the middle with a portion which bears against a depending member I I formed on the arm i0 and which plate is secured on two opposite sides to the frame of the machine. The eccentric 2 further actuates a lever ll, provided with arms I! after the manner of a yoke. The eccentric 2 fits exactly between the arms II. The lever II is mounted on a fixed pivot ll. At the end of the second arm of the lever I I and by means of a gudgeon i6 is articulated the connecting rod 6 provided with a head II which carries the guides 6', 0n the head I1 is secured the member i6 carrying the teeth. The form. the mounting and the configuration of this member, can be varied provided that its contour is formed as an arc of a circle with centre on the axis of oscillation II of the connecting rod I.

The device hereinbefore described can be constructed so as to be inoperative when desired,

- according to the nature of the work to be done by the sewing machine, for example, for sewing a hem with the machine. In such a case, as illustrated in Figure 4, the triangular eccentric 2 is extended on the part opposite the shuttle by a tube or sleeve 2' in which is formed an annular channel in which are engaged the limbs of a manipulating fork member 2". The actuating means may, however, be varied; At the opposite end to thatwhich is provided with a tube orsleeve,

the eccentric 2 is extended to form a truncated portion which facilitates its entry both into the crank l-with asquare-hole I in its head, and between the limbs of the lever I! which forms the lever articulated to the other connecting rod 8, so that thus when it is necessary to hold the teeth of the machine stationary, it sumces to. displace the triangular eccentric 2 so that it does not actuate the corresponding connecting rods 3 and 6.

The eccentric is secured to the shaft I, to move in the direction of rotation of the shaft, by means of a key which can be secured either to the eccentric itself or to the shaft, according to which arrangement is more mechanically convenient.

The device operates in the following manner:- When the shaft I rotates, carrying with it the triangular eccentric 2, the latter, during two nonconsecutive quarters of the revolution actuates the forked lever l3, which causes an ascending and descending movement of the gudgeon IS, on which is mounted the connecting rod 6 carrying the head I! and, with the latter, the toothed member IS. The said mechanism is conveniently guided at its upper part by the guides 6' carried by the head I! and by the circular slider forming the upper part of the connecting rod 3. During the other two quarters of the revolution made by the eccentric 2, which are also not consecutive and are consequently alternate with the first two, the eccentric 2 actuates the connecting rod 3 provided with the square hole 4 and imparts to it an oscillatory up and down movement, and since the circular slider of the connecting rod 3 is pivoted by the spindle i to one end of the link 8 the said circular slider follows a curved path of oscillation with the spindle I as the axis of oscillation.

The circular slider of the connecting rod. 2 which slides between the guides 8' of the head I! of the connecting rod 8 ensures the necessary freedom of movement to the two systems described of which it forms a part.

When the link 8, with the spindle I as axis, oscillates under the action of the spindle I which is mounted on the head or circular slider which moves between the guides 6 of the connecting rod 6, it cannot, owing to the sliding of this system of guides and slider, give to connecting rod 6 an up and down movement since the connecting rod is held at the axis I5. It can thus only move in the direction permitted by the constraint applied to it, that is to say, it can only describe an arc of a circle having as centre the point I5 and whose amplitude is proportional to the value of the horizontal component of the arc described by the spindle 5 whose geometric centre is at the axis of the spindle 1. Further, the pivotal point I of the link 8 can be moved and held stationary by means of the-pivotal adjustment of the shaft 9 which is manipulated by means of the handle Ill-ll with reference to the path of the spindle 5. Therefore, according to the position occupied by the spindle 1, the horizontal component of the are described by the spindle 5 will be nil or will attain its maximum value in one or other direction according to the setting of the said handle.

In fact, when the spindle 1 is at the middle of the part of the path of the spindle I represented by the are a of a circle (Figure 3), as is indicated at B, the horizontal component of the arc described, which in this case will be its minimum, is practically nil, so that the system 8- l|l6 does not move horizontally. There is therefore no horizontal displacement of the teeth nor advance of the material but the group of members indicated effects its vertical up and down movement, since no adjustment is effected of the members of the mechanism producing this movement. When the spindle 1 changes position, following a regulating movement of the shaft 9 effected by means of the handle II, and passes to a position either above or below its neutral point, wherever that position may be, the horizontal component of the path following the arc of a circle described by the spindle I is then followed and is greater according as the adjustment of the spindle 1 is greater. It will be readily understood that, according as the spindle 1 is above or below the neutral position, the level of which is indicated by the shaft 9, the movement nearly level with the platform of the member Figure 3. The shaft luponwhich the eccentric 2 is mounted may either be a shaft provided specifically for the purposeorit may be the shaft which is normally employed to effect the movement of the shuttle'of the-machine.

The "device described can vary as" regards the size and shape of the different members forming it, and also as regards the materials used andas regards its construction and assembly ingeneral, provided that the functional relations between the different parts remain the same.

I claim: i

1. An automatic work-feed device for sewing machines, comprising a toothed feed head, a connecting rod at the one end of which the toothed feed head is mounted, laterally disposed guide surfaces provided on the said connecting rod adjacent to the toothed feed head, a second connecting rod the head of which fits slidably between the said guide surfaces, a rotatable driving shaft, a triangular eccentric mounted on the said shaft, a bell crank lever one arm of which is formed as a fork to engage the triangular eccentric and the second arm of which provides a pivotal axis for the first connecting rod, the disposition of the fulcrum of the bell crank lever and the triangular eccentric being such that during two non-consecutive quarters of a revolution of the eccentric the first connecting rod and with it the toothed feed head move up and down independently of the movement and of the position at any moment of the head of the second connecting rod which constrains the first connecting rod in respect of lateral movement, means for imparting to the second connecting rod from the driving shaft a reciprocating movement and means for determining the path of travel of the head of the second connecting rod in relation to the path of movement of the needle of the machine for the adjustment of the length of the stitch and the direction of the feed.

2. An automatic work-feed device according to claim 1, wherein the second connecting rod is formed with a square opening in which is fitted the trangular eccentric and which is provided with a spindle upon the head of the second connecting rod disposed between the said guide surfaces, a link pivoted to the said spindle, a second spindle of adjustable position parallel with the first spindle, upon which second spindle the link is also pivotally mounted, the said second connecting rod moving up and down duringeach of the two non-consecutive quarters of the revolution made by the eccentric, the said movement being alternate with the movements of the first connecting rod and the head of the second connecting rod being constrained by the said link to follow a path along an arc of a circle about the second spindle, the horizontal component of the movement along the said path causing the first connecting rod and the toothed feed head associated therewith also to follow a feed path which is an arc of a circle struck from the pivotal axis of the first connecting rod on the bell crank lever, the amplitude of the movement along the said feed path depending at any moment on the posi-- tion occupied by the second spindle in relation to the horizontal plane which may be occupied by the two spindles.

, 3. An automatic work-feed device according to claim 1, wherein the second connecting rod is formed with a square opening in which is fitted the triangular eccentric and which is provided necting -rod disposed between the said guide surfaces, a link pivoted on the said spindle, a

second spindle of adjustable positicnfparallel,

with the first spindle, upon which second spindle the'link is also pivotally mounted, the said second connecting rod moving up and'down during each "of the two non-consecutive quarters of the revolution made by the eccentric, the said movement being alternate with the movements of the first connecting rod and theheadof the second rod being constrained by the said link to follow a pathalong an arc of a circle about the second spindle, the horizontal component of the movement along the said path causing the first connecting rod and the toothed feed head associated therewith also to follow a feed path which is an arc of a circle struck from the pivotal axis ofthe first connecting rod on the bell crank lever, the amplitude of the movement along the said feed path depending at any moment on the position occupied by the second spindle in relation to the horizontal plane which may be occupied by the two spindles, and means for varying the position of the second spindle in relation to the said hori-- zontal plane, comprising ,a shaft disposed in the said horizontal plane and in alignment with the centre of the circular path which the second spindle is constrained to follow, an arm upon the said shaft for the support of the second spindle, and a control handle secured to the said shaft for determining the position of the second spindle by rotary adjustment of the said shaft.

4. An automatic work-feed device according to claim 1, wherein the second connecting rod is formed with a square opening in which is fitted the triangular eccentric and which is provided with a spindle upon the end of the second connecting rod disposed between the said guide surfaces, a link pivoted to the said spindle, a second spindle of adjustable position parallel with the first spindle, upon which second spindle the link,

is also pivotally mounted, the said second connecting rod moving up and own during each of the two non-consecutive quarters of the revolution made by the eccentric, the said-movement being' alternate with the movements of the first with a spindle upon the end of the second conconnecting rod and the head of the second connecting rod being constrained by the said link to follow a path along an arc of a circle about the second spindle, the horizontal component of the movement along the said path causing the first connecting rod and the toothed feed head associated therewith also to follow a feed path which is an arc of a circle struck from the pivotal axis of the first connecting rod on the bell crank lever, the amplitude of the movement along the said feed path depending at any moment on the position occupied by the second spindle in relation to the horizontal plane which may be occupied by the two spindles, and means for varying the position of the second spindle in relation to thesaid horizontal plane, comprising a shaft disposed in the said horizontal plane and in alignment with the centre of the circularpath which the second spindle is constrained to follow, an arm upon the said shaft for the support of the second spindle, a control handle secured to the said shaft for determining the position of the second spindle by rotary adjustment of the said shaft, a screw mounted upon the control handle for adjustment radially to the said shaft, means for locking the screw in any position of adjustment in relation to the operating handle, and a plane plate disposed to form a chord of the arc of movement of the operating handle about the axis of the shaft, with which plate the point of the screw in the extreme positions of adjustment of the handle is (Bl-88d to engage.

, 5. An automatic work-feed device according to claim 1, in which the shaft bearing the triangular eccentric is the shaft for effecting movement of the shuttle of the machine.

6. An automatic work-feed device provided with a toothed feed head, a connecting rod supporting the said toothed feed head, a rotatable driving shaft, a triangular eccentric mounted on the said shaft, a bell crank lever one arm of which, is forked to engage the triangular eccentric, a fixed fulcrum pivot for the said bell crank lever, a

pivot upon the second arm of the bell crank lever upon which the connecting rod is pivoted, spaced guide surfaces upon the said connecting rod ad- Jacent to the toothed feed head, a second connecting rod having the one end disposed between the said guide surfaces and engaging the triangular eccentric by means of a square opening, the triangular eccentric being axially movable but non-rotatable on the shaft, one end of the said eccentric being truncated to facilitate en- Rflement with the bell crank lever and the second connecting rod, a sleeve secured to the eccentric, an annular channel in the said sleeve, and an operating fork engaging the said channel.

RAMON cases ROBERT. 

